Dental mixing slab



May 26, 1925.

"r. ROMAINE DENTAL MIXING SLAB Filed May 2, 1924 iNVENTOR ATTORNEY l atented May 25, 1925.

UNITED STATES THEODORE BOMA'INTJ, OF IRVINGTOZN, NEN JERSEY.

DENTAL IVIIXING SLAB.

Application filed May 2, 1924. Serial No. 710,577.

To all whom it may concern.

.lie it known that I, THEODORE R MAINE, a citizen of the United States, residing at Irvington, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Dental Mixing Slabs, of which the following is a speciiication. I

This invention relates to slabs, as used by dentists and others in mixing materials, in limited quantities, for preparing plastic cements or like bite-taking compounds that have quick setting properties and harden very rapidly.

Such cements required quick and dexterous handling and frequently pass the stage of proper plasticity before they can be ap plied, thus necessitating the employment of more than one slab in performing an opera tion extending over any appreciably unusual period of time.

As such cement is strongly adherent to the slab upon which it is mixed, it is not usually possible to delay the operation for the purpose of cleansing the slab, preparator'y'to mixing a fresh quantity of the material, thus increasing the advantages of having several of the slabsready for use.

It is therefore one of the objects of the invention to provide a plurality of relatively thin slabs within a container capable of being used as a support and forming a convenient adjunct to an ofiice or laboratory in which it will be used.

Another purpose is to produce a device in which the slabs are securely held from lateral or longitudinal n'iovement at all times, but which may be instantly raised to present the adjacent underlying slab in position and condition for service.

A further aim is in the provision of a plurality of duplicate slabs, uniform in size and thickness, each having level upper and lower surfaces without irregularities that tend to obstruct the mixing operation or subsequent cleaning.

These several aims and objects are accomplished by the simple and novel construction and arrangement of parts hereinafter described and shown in the accompanying drawing, constituting a material part of this disclosure, and in which Fig. l is a perspective view showing an embodiment of the invention in normal, fully assembled position.

Figure 2 is a transverse sectional view of 7, their curved upper edges being raised at the centers to a uniform height as at 8 and having their fiat inner surfaces disposed'in the planes of the outer surfaces of the body, constituting in effect the corner elements of a frame enclosing the structure.

In order to conveniently raise the apparatus, finger engaging. v recesses 9 are disposed lengthwise centrally in the side surfaces of the body 5. l I The upper surface 1O of the body is smooth and level throughout except for inreaching finger recesses 11in each side and by which the slabs 12 may beconveniently raised. 1

The slabs 12 which are essentially plates, conform to the dimensions of the body 5 in length and width, are of uniform parallel thickness throughout and provided with rounded edges on all sides, these slabs neatly fitting within the corner elements 7 by which they are positioned and held from sliding in any direction.

Any preferred number may be used within the limits of the containing corners 7 four being shown as constituting a set suitable for ordinary purposes.

Due to their rounded edges the slabs may be readily picked up by the fingers of an operator, the lowermost slab being accessible by reason of the recesses 11.

As the slabs or plates 12 are straight and level the cementitious material may be mixed conveniently with a pallet knife or the like, and thereafter the-surfaces scraped and effectively cleansed of, all adherent matter by'ordinary methods.

While any suitable material may be used for the slabs, glass is preferred and the same may be subjected to a considerable degree of heat, as in using gutta-percha, or

to moisture, as Water in saturating and mix ing oxy-phosphate, plaster of Paris and like other dry pulverent substances as used in the art.

From the foregoing it Will be seen that a simple devicefor this purpose has been disclosed in the preferred form of its embodiment, but it is not desired to restrict the details to the exact construction shown, it being obvious that changes, not 1IlV OlV-' ng the exercise of invention, may be made without conflicting with the scope of the appended claims.

7 Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. A mixing slab comprising a thin oblong rectangular body, outstanding frame corners integral therewith and extending to a uniform height thereabove, and .a plurality of plates having rounded edges dis-v posable Within said corners on the upper surface of said body. v

2., A mixing slab comprising a solid oblong rectangular body, parallel in thickness and ofrelative heavy Weight, said body having cushion pads on its lower surface near the corners thereof, integral plate elements at each upper corner of said body extending above the upper edges of the body, and a plurality of uniformly thick plates disposed in tiered'relation on the upper surface of said body ithin the confines of said corner plate elements, said body: having finger recesses in its upper surface extending in from its side whereby 'said' plates may be raised.

3. A'mixing slab comprising a relatively r heavy rectangular base having finger receivingrecesses in opposite sides and other recesses extending from the sides into its upper surface, a plurality of parallel plates uniformlin size With said base, said plates being rounded on each edge, and co-operative means raised from the outer surfaces of said base for causing registration of said plates with said base.

4. A mlxing slabcomprisinga relatively o heavy rectangular base having finger receiving recesses in opposite sides andother recesses extending from the sides into its.

upper surface, cushion pads on the lower,

surface of said base near the corners thereof, a plurality of uniformly thick plates disposable on the upper surface of said base, said plates being equal in area to said upper surface and having rounded edgeson to cause registration of said plates When disposed thereon. a

5. A mixing slab comprising a relatively heavy rectangular base having finger receiving recesses in opposite sides and other recesses extending from the sides into its upper surface, duplicate plates mounted in tier formation on said base, said plates havall sides, and means formed on said base ing rounded edges, and co-operative ele- 

